Acne is a common skin disorder. Many topical and systemic treatment methods are available (“Handbook of Nonprescription Drugs,” American Pharmaceutical Association, 2002, pages 777-791; Katsambas and Dessiniot, Dermatologic Therapy, 21:86-95, 2008). A major shortcoming of the current treatment methods is their slow response often requiring several months of daily application or administration. Furthermore, satisfactory results achieved are often only about 40% to 60% (Chiou, 2007, U.S. Pat. No. 7,258,875 B2). Multiple (3 to 4) treatment steps are often required. Skin dryness and irritation are common; pitting or scarring may occur after treatment. Serious adverse effects can also occur for potent drugs. Although natural polyvalent metal compounds are recently employed to treat acne (Chiou, 2007, U.S. Pat. No. 7,258,875 B2), the stickiness of products due to the glycerin and thickening agent employed is a major drawback not acceptable by many patients in spite of their efficacy (unpublished observation). This is also the case in treating rosacea (Chiou, 2007, U.S. Pat. No. 7,258,875 B2).
The above review indicates a need to develop a new, cosmetically-acceptable, simple, one-step, highly safe and highly effective method for topically treating acne and rosacea without scarring and pitting. Ideally, the new drug treatment may not require a prescription and the same preparation can be used to treat both disorders. The present invention is aimed to achieve the above objectives. This is made possible by a surprising discovery that a commonly used, highly safe and rapidly absorbed (unpublished observation) compound possesses a strong in vitro bactericidal activity against Propionibacterium acnes, that is mainly responsible for the infection in acne. Many other factors are known to contribute to the occurrence of acne and vastly different approaches have been used to tackle the acne disorder. Interestingly, the same compound can also be used to treat infection in rosacea.